Is there a correlation between diet and intelligence?

January 6, 2026 •

4 min read

According to a 2024 study involving children aged 8 to 10, those with better eating habits demonstrated a positive and significant correlation with higher IQ scores. Mounting evidence from multiple studies suggests there is a definitive correlation between diet and intelligence, particularly concerning lifelong cognitive function and development. This relationship is not merely a short-term effect but develops over years and decades, with key nutrients and dietary patterns influencing brain health from early life through old age.

Quick Summary

This article explores the strong connection between dietary choices and cognitive function, examining how specific nutrients, dietary patterns, and the gut microbiome influence brain health throughout life. It highlights the detrimental effects of processed foods and outlines key dietary components that support optimal brain development and function, from childhood through old age.

Key Points

Positive Correlation: Multiple studies confirm a positive correlation between better dietary habits and higher IQ, particularly in childhood.
Long-Term Impact: The effects of diet on intelligence are not immediate but accumulate over years, with poor dietary habits accelerating age-related cognitive decline.
Omega-3s are Critical: Omega-3 fatty acids, especially DHA and EPA, are vital for developing and maintaining brain cell membranes and communication pathways, significantly impacting cognitive function.
Processed Foods are Detrimental: High consumption of ultra-processed foods is linked to faster cognitive decline, inflammation, and altered brain structure due to high sugar and saturated fat content.
The Gut-Brain Connection: The health of the gut microbiome is connected to the brain via the gut-brain axis, influencing neural development, inflammation, and neurotransmitter production.
Mediterranean and MIND Diets Protect: Dietary patterns like the Mediterranean and MIND diets, rich in vegetables, fruits, and healthy fats, are consistently associated with a lower risk of cognitive decline and dementia.
B Vitamins are Essential: B vitamins, including B6, B12, and folate, are critical for energy metabolism, neurotransmitter synthesis, and managing homocysteine levels linked to cognitive decline.

The Foundational Role of Nutrition in Early Brain Development

During pregnancy, infancy, and early childhood, the brain undergoes its most rapid development. Adequate nutrition during these critical periods is paramount for laying the groundwork for lifelong cognitive function.

The Critical Importance of Omega-3 Fatty Acids

Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), types of omega-3 fatty acids found abundantly in fatty fish, are crucial for proper brain growth and function.

Support for Neuronal Health: DHA is a major structural component of brain cell membranes. It preserves membrane health and facilitates efficient communication between neurons.
Role in Neurogenesis: Omega-3s promote the growth of new nerve cells (neurogenesis) and protect against inflammation, supporting synaptic plasticity—the brain’s ability to form new connections.
Enhanced Cognitive Outcomes: Studies link adequate maternal omega-3 intake with better cognitive development and higher intelligence scores in children, while deficiency is associated with impaired learning and behavior.

The Negative Impact of Processed Foods

While a nutrient-rich diet can boost cognitive potential, diets high in ultra-processed foods (UPFs), sugar, and saturated fats have been consistently linked to poorer brain function and increased risk of cognitive decline.

Accelerated Cognitive Decline: A 2022 study involving thousands of Brazilian adults found a 28% faster rate of cognitive decline in those whose diets contained over 20% of calories from UPFs.
Inflammation and Brain Health: Processed foods trigger systemic inflammation and insulin resistance, which have a demonstrated negative effect on brain health, particularly in areas responsible for memory and executive function.
Altered Brain Circuitry: Research using brain imaging has revealed that high UPF intake can alter the microstructures of brain regions associated with feeding behavior, potentially rewiring reward circuits and promoting overconsumption.

The Gut-Brain Axis: A Key Communication Pathway

The gut microbiome, the complex community of microorganisms residing in the intestines, plays a surprising yet significant role in brain function through the gut-brain axis. This communication system involves neural, immune, and endocrine pathways that connect the digestive system to the central nervous system.

How Gut Bacteria Influence the Brain

Production of Neurotransmitters: Certain gut bacteria produce neurotransmitters and other neuroactive substances, including serotonin, that can directly influence brain function and mood.
Modulation of Inflammation: Beneficial gut microbes produce short-chain fatty acids (SCFAs), which have anti-inflammatory effects and help maintain the integrity of the gut barrier, preventing toxins from entering the bloodstream.
Influence on Brain Development: Studies on germ-free mice show altered brain development, suggesting that the gut microbiome is vital for proper neural development and can affect memory and behavior.

Comparing Brain-Healthy Diets

Different dietary patterns have been studied for their effects on cognitive health, with some showing more protective effects than others. The Mediterranean and MIND diets are two of the most well-researched.


Feature	Mediterranean Diet	MIND Diet
Core Components	Fruits, vegetables, whole grains, legumes, nuts, seeds, olive oil, fish (frequent), limited red meat and sweets.	A hybrid of the Mediterranean and DASH diets, emphasizing green leafy vegetables, berries, whole grains, nuts, fish, and olive oil.
Key Focus	Overall healthy eating pattern, linked to better cognitive performance and lower dementia rates in some studies.	Specifically targets reducing risk for neurodegenerative diseases like Alzheimer's. Associated with a significantly slower cognitive decline.
Research Findings	Meta-analysis found high adherence linked to a lower risk of mild cognitive impairment (MCI) and Alzheimer's disease (AD).	One study found high adherence associated with a 53% reduced rate of AD compared to low adherence.

The Impact of B Vitamins and Other Micronutrients

Micronutrient deficiencies can have a profound impact on cognitive function, especially during critical developmental stages. B vitamins play a pivotal role in brain health.

Homocysteine Reduction: B vitamins (B6, B12, and folate) help break down homocysteine. High levels of this amino acid are linked to brain atrophy, cognitive decline, and increased risk of dementia.
Neurotransmitter Synthesis: Vitamin B6 is essential for creating key neurotransmitters such as serotonin and dopamine, which regulate mood and cognition.
Energy Metabolism: B vitamins, particularly B1 (thiamine), are critical co-enzymes in the metabolic processes that generate energy for brain cells. A deficiency can lead to neurological problems.

Conclusion: A Clear Link, Not a Magic Pill

While a genetic component influences intelligence, a vast and growing body of evidence confirms a strong correlation between diet and intelligence, affecting cognitive function throughout the lifespan. This relationship is not driven by a single 'superfood' but rather by a holistic, nutrient-dense eating pattern. Diets rich in omega-3 fatty acids, antioxidants from fruits and vegetables, and whole grains, like the Mediterranean or MIND diets, support brain health by promoting cellular repair, reducing inflammation, and maintaining a healthy gut microbiome. Conversely, diets dominated by ultra-processed foods accelerate cognitive decline and have been shown to negatively impact brain structure. The correlation between what we eat and our cognitive health is undeniable and highlights the profound, long-term impact of dietary choices on our most complex organ.

Frequently Asked Questions

A child's diet significantly impacts brain development during critical growth phases. Studies show a positive correlation between good eating habits (rich in fruits, vegetables, and fish) and higher IQ scores, while diets high in processed foods may hinder development.

While a healthy diet has minimal short-term effects on intelligence in healthy adults, long-term adherence to a nutritious eating pattern can prevent or slow age-related cognitive decline. It supports brain function over decades, rather than providing an immediate boost.

Omega-3s, specifically DHA and EPA found in fatty fish, are crucial for building brain cell membranes and facilitating communication between cells. They support neural development and plasticity, and deficiency is linked to impaired learning.

Yes. Research consistently links high consumption of ultra-processed foods to faster cognitive decline, increased inflammation, and changes in brain regions that regulate appetite and reward. The negative effects are cumulative over time.

The 'gut-brain axis' is a communication network connecting the gut to the brain. Gut microbes produce neurotransmitters and anti-inflammatory compounds that affect brain development, mood, and cognitive abilities. Poor gut health can contribute to inflammation that negatively impacts the brain.

Both diets are highly beneficial for brain health. The Mediterranean diet, rich in healthy fats, fish, and produce, is linked to a lower risk of mild cognitive impairment and Alzheimer's. The MIND diet, a hybrid of the Mediterranean and DASH diets, specifically targets and has been shown to slow cognitive decline.

B vitamins, including B6, B12, and folate, play vital roles in neurotransmitter synthesis, energy production for brain cells, and breaking down harmful homocysteine. Deficiencies, especially in B12 and folate, are associated with cognitive decline.